This invention relates to stringed musical instruments, and deals more particularly with an improved machine head for use in attaching one end of a string to an instrument and in tensioning the string to tune it to a desired pitch.
Machine heads of the type with which the invention is concerned are commonly used as Parts of guitars, banjos and similar stringed musical instruments and are usually located on a peg head located at the outer end of the instrument's neck with each machine head being arranged to receive one of the strings of the instrument and being operable by manual rotation of an associated handle or thumb piece to tension the string so as to bring it to and hold it at a desired pitch.
The pitch or frequency of vibration of a string is very much dependent on its tension with the result that very small changes in tension produce changes in pitch which are detectable by ear. Since a machine head includes a string post to which the associated string is attached and on which the string is wound by rotation of the post about its longitudinal axis to tension the string in the tuning process, it is therefore desirable that the post have a very stable axis of rotation. That is, the post should ideally be limited to only rotational movement about its longitudinal axis and should be restrained against all other movements so that no unwanted deviation in string tension and pitch will be caused by wobbling or other erratic movement of the post.
The general object of this invention is therefore to provide an improved machine head wherein the string post is supported so as to be readily moveable in either direction about its longitudinal axis for purposes of tensioning or detensioning the associated string for tuning purposes, with the post being otherwise restrained so as to have little or no freedom of movement or play in any other direction, thereby resulting in the machine head having the ability to very smoothly increase or decrease the pitch of the associated string as the post is turned and to reliably hold the string at the selected pitch.
Other objects and advantages of the invention will be apparent from the following description and drawings describing and illustrating a preferred embodiment of the invention and from the accompanying claims.